Porous carbonized composite material for high-performing silicon anodes

Patent metadata

Field	Value
Publication number	US-2017092950-A1
Application number	US-201514868878-A
Country	US
Kind code	A1
Filing date	Sep 29, 2015
Priority date	Sep 29, 2015
Publication date	Mar 30, 2017
Grant date	—

Abstract

An electrode material for an electrochemical cell, such as a lithium ion battery or a lithium sulfur battery, is provided. The electrode may be a negative anode. The electrode material comprises a composite comprising a porous matrix comprising a carbonized material. The electrode material further comprises a plurality of silicon particles homogeneously dispersed in the porous matrix of carbonized material. Each silicon particle of the plurality has an average particle diameter of greater than or equal to about 5 nanometers and less than or equal to about 20 micrometers.

First claim

What is claimed is:

1 . An electrode material for an electrochemical cell comprising:
an electrochemically active composite comprising:
a porous matrix comprising a carbonized material; and
a plurality of particles comprising silicon homogeneously dispersed in the porous matrix, each particle of the plurality has an average particle diameter of greater than or equal to about 5 nanometers and less than or equal to about 20 micrometers.

2 . The electrode material of claim 1 , wherein the plurality of particles comprising silicon is capable of accepting the insertion of lithium ions during charging of the cell or battery and releasing lithium ions during discharging of the electrochemical cell or battery.

3 . The electrode material of claim 1 , wherein at least a portion of a surface of each particle of the plurality is coated in a layer of the carbonized material.

4 . The electrode material of claim 1 , wherein the porous matrix of carbonized material comprises a plurality of hierarchy composite particles having an average particle diameter of greater than or equal to about 5 nanometers and less than or equal to about 20 micrometers.

5 . The electrode material of claim 1 , wherein a loading density of the plurality of particles in the porous matrix of carbonized material is greater than or equal to about 0.1 mg/cm 2 and less than or equal to about 20 mg/cm 2 .

6 . The electrode material of claim 1 , wherein a packing density of the plurality of particles in the electrochemically active composite is greater than or equal to about 5% and less than or equal to about 90% by volume.

7 . The electrode material of claim 1 , wherein the packing density of the plurality of silicon particles in the electrochemically active composite is greater than or equal to about 5% and less than or equal to about 75% by volume.

8 . The electrode material of claim 1 , wherein at least a portion of the plurality of particles are chemically bonded to the carbonized material.

9 . An electrochemical cell comprising:
a negative electrode comprising the electrode material of claim 1 ; a positive electrode; a separator; and an electrolyte.

10 . The electrochemical cell of claim 9 , wherein the negative electrode is substantially free of carbon black particles.

11 . The electrochemical cell of claim 9 , wherein the positive electrode comprises an electrochemically active sulfur-containing material.

12 . A method of making a negative electrode material for an electrochemical cell, the method comprising:
reacting an acid having a pH of less than or equal to 3 with an admixture of a silicon-containing precursor and a sugar to form a solid porous composite precursor material; and heating the solid porous precursor composite material to a temperature greater than or equal to about 500° C. and less than or equal to about 900° C. for a duration of greater than or equal to about thirty (30) minutes to form a porous composite electrode material comprising a matrix comprising a carbonized material and a plurality of homogeneously dispersed particles comprising silicon distributed therein.

13 . The method of claim 12 , wherein the silicon-containing precursor is a powder with an average particle diameter of greater than or equal to about 5 nanometers and less than or equal to about 20 micrometers.

14 . The method of claim 12 , wherein the sugar is selected from the group consisting of: sucrose, maltose, lactose, fructose, glucose, galactose, and combinations thereof.

15 . The method of claim 12 , wherein the sugar comprises sucrose (C 12 H 22 O 11 ).

16 . The method of claim 12 , wherein the acid comprises sulfuric acid (H 2 SO 4 ).

17 . The method of claim 12 , wherein the admixture of the silicon precursor and the sugar has a weight ratio of silicon to sugar of 1:4 to 9:1.

18 . The method of claim 17 , wherein the admixture of the silicon precursor and the sugar has a weight ratio of silicon to sugar of about 1:1.

19 . The method of claim 17 , wherein the weight ratio of the silicon and sugar mixture to the acid is in a range of 10:1 to 1:1.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Xiao Xingcheng
• Zhou Weidong

Classifications

• H01M4/364 Primary

  as mixtures · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/587 Primary

  for inserting or intercalating light metals · CPC title